|Iversen, William - Bill|
|BLODGETT, SUSAN - Iowa State University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2012
Publication Date: 6/26/2012
Publication URL: http://handle.nal.usda.gov/10113/57103
Citation: Lenssen, A.W., Iversen, W.M., Sainju, U.M., Caesar, T., Blodgett, S.L., Allen, B.L., Evans, R.G. 2012. Crop yield and quality, weeds, insects, and water use of durum and selected brassicaceae oilseeds in two-year rotations. Agronomy Journal. 104:1295-1304.
Interpretive Summary: Oilseed entries varied for yield of seed and oil, with canola-quality B. juncea having higher levels than camelina or crambe. Water use of oilseeds was similar among entries, but WUE of B. juncea was superior due to its higher yield. Overall, water use of oilseed entries and durum following oilseeds was similar, indicating that these crops used most of the available soil water in this semiarid environment. Oilseeds differed for arthropod infestations, documenting that management will likely differ by oilseed species. All crucifers had substantial and diverse weed communities, but density and biomass were highest in crambe at harvest. However, weeds were easily managed in durum. Nevertheless, development of improved weed management systems is necessary for oilseeds in two-year rotations with durum. Development of oilseeds with enhanced seedling vigor, combined with integrated cultural and herbicide systems, likely would improve competitiveness with weeds, resulting in improved seed and oil yields and WUE. Durum productivity and water use was similar when following these diverse oilseeds, but yield and water use were higher when following summer fallow. Two-year oilseed-durum rotations can be utilized for production of grain and biofuel feedstock. However, production systems optimization and testing for sustainability will require additional research.
Technical Abstract: Cool-season oilseeds are potential feedstock for biofuel production, but few studies have compared oilseed-durum (Triticum durum Desf.) rotations. We conducted a field trial under dryland conditions for 2007-2010 near Froid, Montana, comparing productivity, water balance, and key weed and arthropod pests of two-year oilseed-durum rotations under zero tillage. Rotations included durum with three Cruciferae, camelina (Camelina sativa (L.) Crantz), crambe (Crambe abyssinica Hochst. ex R.E. Fries), and canola-quality Brassica juncea L., and chemical fallow. Over four years, B. juncea had the highest seed and oil yields of crucifer entries. Water use was similar among oilseed entries, averaging 286 mm. Water use was similar for durum following oilseeds, averaging 282 mm, 72 mm less than for durum following fallow. Durum following chemical fallow averaged 775 kg ha-1 higher grain yield than durum following oilseeds due to higher water availability and use. Camelina averaged greater weed biomass at harvest and lower densities of Plutella xylostella L. than other oilseeds. Durum in rotation with crambe had higher weed density and weed biomass at harvest than durum following B. juncea or fallow. Canola quality B. juncea generally performed better than crambe or camelina, but each oilseed entry had several positive attributes. Oilseed-durum rotations can be utilized for biofuel feedstock and grain production, but determination of long-term sustainability of two-year rotations requires additional research.